foreach $server (@servers) {
  chomp $server;
  open TMP, ">/tmp/$server.tmp";
  $ENV{"FILENAME"} = "/tmp/$server\.tmp";
  foreach(@DATA) {
    ($hostid, $time, $get, $post, $currconn) = split(/\t/);
    next if ($hostid ne $SERVER{$server});
    ## more here...
  }
  close TMP;
}